I Aim to Misbehave
by The Bushranger
Summary: After 450 years, Dani Phantom will fly again. FireflySerenity crossover. DxS. Character death.


_Told during "Serenity", on Miranda during Mal's speech. Spoilers for the movie. A bit AU for the Firefly 'verse..._

_Warning: Character death._

* * *

**"I Aim to Misbehave" **

_This report is maybe 12-years-old._

It had been four hundred and fifty years since the Fall. Since mankind had fled Earth-that-was. Since Danielle Fenton had been able to fly free.

It had only been five years after she'd met Danny before he was dead. Plasmius had finally snapped, assembled an army of mind-controlled ghosts, and gone after Amity Park with a full-out attack.

_Parliament buried it, and it stayed buried 'till River dug it up._

It had taken all they had to defeat it. The two other halfas had finally mutually obliterated themselves, releasing the ghosts from Vlad's control. Most of them immediately left, outraged at having been used. A few fought on, to be quickly neutralized, but Danny was dead, gone, leaving behind his bride and infant son. He'd made her promise that she'd go on with her life if he didn't make it.

/ flashback /

_"No matter what happens, I want you to live, Sam." He turned her tear-stained face up to his. "Live, for me."_

/ end flashback /

Life went on, but Sam never really recovered. Maddie took them in, and helped raise Daniel Junior. They watched him carefully to see if his father's ghost powers had been passed on, but aside from unnaturally green eyes and unusually quick healing and reflexes, he was completely human.

_This is what they feared she knew._

A few years later, Dani realized she was no longer aging. Whether this was a natural part of being a halfa or the result of the cloning process was never determined, but no matter how many years passed, she'd remain with the appearance of a girl in her early twenties.

For forty-five years, things were remarkably quiet on the ghost front. The Plasmius Portal had been destroyed, and the Fenton Portal was permanently closed.

Then, the Government Portal was opened.

_And they were right to fear because there's a whole universe of folk who are gonna know it, too._

The Fentons had refused to turn over ghost-portal data to the government, stating that they didn't want it used for "immoral purposes". The Guys in White - later absorbed by the NID - had had to start from scratch. Finally they successfully created their own portal to the Ghost Zone. The only problem was, they hadn't installed any sort of shield to close it.

Thousands upon thousands of ghosts, who had been waiting for years for the chance, poured through the portal, quickly overwhelming all defenses. It was quickly realized that there was no way that the planet could be saved. Fortunately there had been an active "cover" for the ghost portal work - the construction of a large portal in orbit, for the purposes of determining if extradimensional travel was possible; and over the years commercial spaceflight had become virtually commonplace.

The decision was made: Earth was to be evacuated.

_They're gonna see it._

The final stand, defending the evacuation fleet, was outside of Chicago. Thousands of ghosts launched wave after wave of attacks against the ghost-shielded transports, while a combination of military forces and ghost hunters did their best to beat them back.

Counting herself, there were a mere four ghosts who actively fought to help the humans.

She was the only one who'd made it out.

_Somebody has to speak for these people._

Dora had been the first to go down. Her amulet was ripped away by Walker; a moment later a Fenton Bazooka round meant for the spectral sheriff threw them both into the Ghost Zone. Ember's demise had been even more tragic: an unknown ghost overshadowed one of the government troopers, who then turned and shot her squarely in the chest with a Fenton Disintegrator. The last Dani had seen of Wulf, he was being smothered by a pile of at least a hundred ectopusses.

As the last few ships began to lift off, now few enough in number that the landing field could be covered by a small yet extra-strong ghost shield, Dani desperately tried to get aboard one of them. It was quite clear that if she remained behind her fate would be far worse than death, but despite all she'd done to protect them, all the panicked evacuees saw her as was a ghost. Four ships shot at her with ectolasers, while another captain actually pulled out a sawed-off shotgun. It was literally the very last ship to leave that finally hauled her, exhausted, aboard.

_You all got on this boat for different reasons, but you all come to the same place._

The family who owned the ship took her in, and during the four months' journey to find a new system for humanity's home after passing through the portal, they had plenty of time to hack into government systems. All mention of Danielle Fenton, halfa - and, being a ghost, _persona non grata_, in fact if not officially - was erased, replaced with Danielle Rosenburg, college student.

The fresh start was necessary for another reason; her name reminded her too much of those she had lost, who had grown old while she remained forever young. Sam had suffered a fatal stroke upon hearing the news about the Government Portal. Jazz had been the one to volunteer to remain behind, to operate the orbital portal - and to destroy it afterwards.

Danny Junior and his family had disappeared in the chaos, and were never seen again.

_So now I'm asking more of you than I have before. Maybe all._

For the next few centuries, she'd drifted from world to world and identity to identity as civilization was rebuilt. With all work on dimensional portals banned, along with ectoscience in its entirety, there slowly evolved an odd mix of twenty-second and nineteenth century technology and ways.

She never used her ghost powers publicly. Occasionally, when she was alone at night, she'd fly around the house she was living in at the time, but that was it. At first it was because of the general fear of ghosts, and what would be done to her if anyone found out the truth. Later, it had become a habit.

Virtually everyone forgot about the details of the flight from Earth-that-was. The enemy wasn't ghosts, everyone knew ghosts weren't real. Overcrowding drove mankind from its cradle. Very few knew the truth about ghosts - and Dani was the only one remaining who remembered the dimensional jump.

_Sure as I know anything I know this, they will try again._

But, it seemed, not everyone in the Alliance was ignorant to the truth. Her current persona was a mercenary pilot; she'd done more than her share of work in the borderlands, and she'd run into Reavers a couple of times. Each time had left her with a chillingly familiar feeling - it wasn't her ghost sense, it wasn't nearly intense enough for that, but it was certainly something similar.

When the bulletins had gone out announcing the bounty on the Tams, she'd done some digging, pulling in old contacts to find out why. What she'd found had chilled her to the bone.

She'd followed _Serenity_ for months, finally managing to cross paths with the elusive Captain Reynolds. It had taken some negotiating, but she'd signed on as crew, and it had only taken one look at River Tam to confirm her suspicions. The girl's eyes were an unnatural shade of green - the same color as Danny Junior's, so many years ago.

_Maybe on another world, maybe on this very ground swept clean._

For years, she'd stayed hidden. During the Unification War, she'd laid low, not willing to risk being captured and exposed...and not wanting to have it on her conscience that people had died, because of her actions, that she could have saved by using her powers.

Now here she was on Miranda, with the truth of the Reavers staring them all in the face. She'd bet her last dollar that the "pax" drug had used some sort of ectotech, that would explain how she was able to feel the Reavers, as much or even more so than River did, although she'd never said anything to protect her secret.

It was obvious that somebody in the Alliance still had ghost knowledge, and was experimenting with it, somehow genetically tweaking the Academy students. Were they simply trying to enhance humans? Or were they actually trying to create a halfa? Was a new Ghost Portal being constructed? If so, how long until they finished it?

_A year from now, 10, they'll swing back to the belief that they can make people . . . better. And I do not hold to that._

There was an additional personal factor: the Alliance had been responsible for the death of Shepherd Book. While she had never had the chance to get to know the man very well personally, she'd known his reputation - and she'd known who he was.

He'd been the last known direct descendant of Tucker Foley.

So what now?

_So no more running._

The choice was obvious: the last disaster had been caused by secret agencies meddling with things they didn't understand, that they should have left alone. It was happening again. It had to be stopped.

There was nothing else to be done. The Alliance had proven itself evil one too many times. It had to come down – and it was going to start here.

The gloves were going to come off. After over four centuries of forced retirement, Dani Phantom would fight again.

And it felt _good_.

_I aim to misbehave._

* * *

_Butch Hartman is the one making money off of Danny Phantom's name and likeness.  
Firefly and Serenity belong to Joss Wheldon/Mutant Enemy, Universal, and 20th Century Fox.  
Buffy the Vampire Slayer belongs to Joss Wheldon/Mutant Enemy and 20th Century Fox.  
Stargate: SG-1 belongs to MGM, Gekko, Double Secret Productions, Showtime and the Sci-Fi Channel.  
The Plot Were-Bunny inspired by "Wallace & Gromit: The Curse of the Were-Rabbit", which belongs to Nick Park, DreamWorks and Aardman Animations._

_Please take a moment to post a review; it's a beautiful thing._


End file.
